package com.template.config;


import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;


/**
 * 登录检查
 */
public class LoginHandlerInterceptor implements HandlerInterceptor {

    /**
     * 目标方法执行之前
     *
     * @param request
     * @param response
     * @param handler
     * @return
     * @throws Exception
     */
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {

        //  登录检查逻辑
        HttpSession session = request.getSession();

        Object loginUser = session.getAttribute("loginUser");

        if (loginUser != null) {
            //  有登录信息，不进行拦截操作
            return true;
        }

        //  未进行登录，进行拦截操作，并自动跳转到登录界面
//        session.setAttribute("msg", "当前未进行登录");
//        response.sendRedirect("/");
        request.setAttribute("msg", "当前未登录");
        request.getRequestDispatcher("/login").forward(request,response);
        return false;
    }

    /**
     * 目标方法执行完成以后
     *
     * @param request
     * @param response
     * @param handler
     * @param modelAndView
     * @throws Exception
     */
    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {

    }


    /**
     * 页面渲染完成以后
     *
     * @param request
     * @param response
     * @param handler
     * @param ex
     * @throws Exception
     */
    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {

    }
}
